Brief Summary

Drumming Katydid (Meconema thalassinum)

Identification: A tiny katydid with a tympanum fully exposed on each foretibia. Forewings longer than hindwings. No stridulatory area apparent at base of male forewings. Length 14-19 mm.

Habitat: Deciduous trees and the vegetation beneath.

Season: July–Oct. One generation per year.

Song at 25°C: Males call at night by rapidly tapping one of the hind feet on the substrate, such as the surface of a leaf. The pad under the first tarsal segment of the male is hardened while that of the female is soft. The sound varies with the substrate but under favorable conditions it can be heard 12 feet away. A bout of drumming consists of several bursts, the initial ones being brief and the later ones lasting about 1 s. Foot impact frequency is ca. 43/s.

Similar Species: Meadow katydids (Conocephalinae) have the tympanum visible only through slits in the expanded foretibia; males have conspicuous stridulatory areas on the forewings. False katydids (Phaneropterinae) are larger and the hindwings are often longer than the forewings.

Remarks: The drumming katydid is native to Europe. It lays its eggs in crevices in bark and may have been imported to the United States as eggs on woody ornamental plants. Whatever the means, by 1957 it had become established on western Long Island, New York, and by 1980 it had extended its range to Rhode Island and to Scarsdale and Ithaca, New York. It has since been reported as far east as Michigan in the northeast U.S. and in several localities in the vicinity of Vancouver on the West Coast.

No function has been proved for the male's drumming, and either the air-borne or the substrate-transmitted vibrations might be the more important. Stridulation, using minute teeth on the forewings, may also occur. If so, the signal is likely ultrasonic.